Design and Implementation of Token-Based Authentication Using OAuth2 and JWT

When enterprise applications proliferate, isolated user data creates information silos; a unified, standardized account management system becomes essential for platform evolution, enabling single sign‑on, third‑party login, and cross‑system resource access.

Terminology defines third‑party application (client), HTTP service (service provider), resource owner (user), user agent (browser), authorization server, and resource server.

Research background describes traditional monolithic authentication using sessions versus modern token‑based authentication, highlighting token advantages: stateless server, better performance, and support for mobile and cross‑domain access.

Research objectives aim to achieve flexible, standardized security authentication across heterogeneous systems through a standard token workflow.

The typical token authentication process includes: (1) user submits login credentials to the authentication service; (2) the service validates credentials and returns an access token with user info; (3) the client includes the token in HTTP headers for API calls; (4) the called microservice validates the token; (5) the service returns the requested resources.

Key security functions cover token acquisition, login authorization, access verification, and token renewal.

Technical selection adopts OAuth2 password grant as the authorization standard and JWT as the token format.

Authentication flow logic details system authorization (token issuance) and system authentication (token validation) with accompanying diagrams.

Interface design outlines endpoints for obtaining authorization credentials and for token renewal, emphasizing client registration and credential verification.